Regioselective Preparation of Functionalized Isoxazoline Derivatives, Key Intermediates in the Synthesis of Selective NMDA Receptor Antagonists

Two highly versatile isoxazoline derivatives, as key intermediates for the synthesis of differently functionalized subtype-selective N-methyl-d-aspartate receptor antagonists, were designed and synthesized. The synthetic strategy is based on an intramolecular nitrile oxide cycloaddition reaction which is a powerful method capable of controlling both the regio- and stereochemistry of the pericyclic reaction.